Solar panels for sensor nodes

Intro For a while now, I started replacing the dead AA(A) batteries in my sensor nodes with rechargeable NiMH ones. So, since these batteries are rechargeable, I thought, why not trying adding small solar panels for sensor nodes, where light is abundant. Node 27: outside sensor Purpose: outside temperature, humidity, light, pressure sensor. Powered by 2 x AAA 500mAh from Ikea. The solar cell is rated 3V, 125mA and is pointing vertically south and costs… Continue reading

Simple LED strip UPS – closed.

Update after 3 months The UPS is functioning as it should, and I think the solution is viable as a simple, low cost UPS where it is needed. It was a good mind and build exercise, but there are two reasons why I am not keeping it: First – realistically speaking, electricity fails way too seldom to actually use it.  Second, unless I build one of these for each room, I will always have to… Continue reading

An odd torch – Energizer Pivot

Intro I have used 2 types of LED torches: regulated and unregulated. The unregulated ones are the most common and they use some simple circuits for the LEDs, which means that as the battery discharges the light output gets lower. The regulated ones use some circuit to maintain a constant current flow as the battery discharges, for as much as possible. What about the Energizer hard case pro pivot plus? This is an odd one.… Continue reading